The invention relates generally to the field of faceplate assemblies used to hold a workpiece for wood turning operations, and more specifically to the field of faceplate assemblies of non-unitary construction, where the workpiece holding member is separable from the lathe attachment member. The invention further relates to a method of wood turning where the steps of separation and reattachment of the workpiece holding member from the lathe attachment member are part of the method.
In wood turning operations the workpiece, i.e., a piece of wood to be shaped, is attached to a lathe. The workpiece is then rotated while various cutting or scraping implements are pressed against the workpiece to remove the undesired wood to shape the workpiece into the final product, such as a bowl or a vase. The rotation method assures much greater symmetry than trying to carve from a stationary workpiece. Because of the rotation speeds and the pressure exerted against the workpiece during the shaping process, a secure attachment of the workpiece to the lathe is essential. One of the standard mechanisms for attaching the workpiece to the lathe is a one-piece work holder consisting of an internally threaded mounting hub centered on the back of a relatively larger diameter planar disk. The hub threads onto the threaded spindle of the lathe itself and the workpiece is attached to the planar surface of the disk by suitable method, such as screws inserted through apertures in the disk or adhesive. When the lathe spindle is not threaded, another standard mechanism is a one piece work holder of hub and disk having a set screw mounted in the hub for tightening into the side of the lathe spindle. Still another standard mechanism, used with lathe spindles which are tubular, with the internal opening tapering inwardly, is to insert a one-piece work holder having a tapered shaft into the spindle, where it is held in place by friction.
While a standard one-piece work holder is adequate with regard to securing the workpiece to the lathe, its use presents numerous inconveniences and problems. These problems are overcome by the invention. When performing wood turning operations it is often necessary to remove the workpiece from the lathe a number of times. This can be for any of several reasons. For example, it is often desirable to begin working with green wood, i.e., wood that has not been fully dried, since the cutting and shaping operations can be performed more effectively. At various stages during the wood turning process, the wood must be allowed to dry, which can take anywhere from three weeks to three months depending on the remaining thickness of the wood. To work on a number of pieces, a worker using a one-piece work holder must either have a large number of relatively expensive work holders, or the individual work holder must be removed from the workpiece during this drying period and used on another workpiece. Removal of the work holder causes two problems. Since the wood is now no longer attached to the planar surface of the disk, it usually warps during the drying stage. This requires the workpiece to be planed down and re-centered prior to reattachment. Also, removing the workpiece and reattaching it to the work holder results in a weaker attachment, since the screw holes in the bottom of the workpiece become enlarged or softened. This is dangerous to the worker, should the workpiece fly loose from the lathe during the turning operations.
Another situation requiring removal of the workpiece form the lathe is where a number of workers must use the same lathe. This can occur, for example, in a school or small industrial shop setting. Again, unless a number of work holders are kept available, a one-piece work holder requires that each individual workpiece be removed and reattached numerous times, so that the work holders are available to other users for their workpieces. Additionally, there are situations where a shop has a number of lathes of different makes or dimensions, each having a different size attachment spindle. To work the workpieces on different lathes, the worker must detach the workpiece from a work holder of one particular hub size and attach a work holder of differing hub size.
The invention solves these and other problems by providing a device and a method of wood turning using the device where the workpiece is never detached from the work holding member of the device. The device comprises a workpiece holding faceplate which is removably attachable to a mounting hub. The faceplate can be attached to any hub, even hubs of different size for use with different lathes. The faceplates can be produced for one-fifth to one-tenth the cost of the one-piece work holders, so a school or shop can economically have a large number of faceplates on hand to be used with a small number of hubs, since only one hub per lathe is be required. Since the faceplates remain attached to the work pieces throughout the operation, the problems of warping and unsafe reattachment are alleviated.
It is an object of the invention to provide a work holding assembly comprising a faceplate removable from and reattachable to a lathe mounting hub, such that the faceplate remains attached to the workpiece when removed from the lathe and the hub remains mounted on the lathe.
It is a further object to provide such an assembly where any one of a number of similar faceplates can be attached to a hub.
It is a further object to provide such an assembly where the faceplate can be attached to any one of a number of different hubs sized for particular lathes.
It is another object of the invention to provide a method of wood turning utilizing an assembly comprising a faceplate removable from a lathe mounting hub, such that the faceplate remains attached to the workpiece when removed from the lathe and the hub remains mounted on the lathe, the faceplate and workpiece to be remounted on the lathe hub at a later time.